More than 2000 great whites off WA: Study

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A WORLD-FIRST study suggests there may be more than 2000 adult great white sharks off WA’s beaches — more than twice the number on the east coast.

Preliminary results from an investigation by CSIRO have found white shark numbers in WA are not increasing, but are steady, despite warnings from environmentalists that the predators are endangered.

Federal Environment Minister Josh Frydenberg has used the results to call on WA to look again at tougher measures to safeguard WA beachgoers, such as nets and drum lines.

“Couple these higher numbers with the 15 fatal shark attacks over the last 17 years in WA and it’s clear the State Government needs to look seriously at more rigorous and proactive measures to protect its citizens from shark attacks,” Mr Frydenberg said.

“The Queensland and NSW governments have had in place extensive measures to manage sharks for a number of years.”

The study, the first government-led examination of white shark numbers in Australian waters for decades, was ordered by Mr Frydenberg after a series of shark attacks in WA and the east coast. It used a new technique to take genetic samples from juvenile white sharks off Port Stephens in NSW to determine the number of breeding animals in the east coast population, which is distinct from those in WA and South Australia.

Based on those results, the scientists were able to estimate the “south-western” population of white sharks for the first time.

The CSIRO estimates the adult population in the west is between 750 and 2250, with the animals having a 90 per cent survival rate year to year.

The total population is significantly bigger when juvenile animals are taken into account.

There were far fewer adult numbers in the east, with 470 to 1030 white sharks surviving at an annual rate of 93 per cent.

Queensland, which has had a shark-control program using drum lines and nets since 1962, has had just one shark-related fatality at a protected beach in that time.

NSW has had mesh nets at more than 50 beaches with no fatalities at a protected beach since 1951. More recently, NSW has also started using so-called smart drum lines as a non-lethal means to protect the public.

The Barnett government stopped using drum lines after an outcry by activists. The McGowan Government has rejected the use of drum lines and nets, instead funding a subsidy for personal deterrent devices. The Federal Government said the preliminary estimates would be peer reviewed and could change.